Wave Morph circuit by Motohiko Takeda ,following a method proposed by Osamu Hoshuyama ,the page describing the whole process and analysis of the circuit is here http://www.aleph.co.jp/~takeda/radio/morph/ featuring a demo - video capture of the wave morph in action ,from there the short description by Motohiko :

This is wave form convert. It can convert saw wave from saw to triangle and anti saw by CV in seamless.